Thermal processing of Pacific salmon in steam/air and water-immersion still retorts: Influence of container type/shape on heating behavior

The effect of container type/shape (semi-rigid rectangular thin profile pla stic container (SPC) vs, cylindrical metal can (CMC) of the same volume), t ype of heating medium (steam / air vs. water) and retort temperature (110, 120 and 130 degrees C with an air-ovrerpressure 70 kPa) on the heating beha vior (heating and cooling rate indexes and lag factors, lethality (F-0) coo k value (C-0) and cook value-to lethality ratio) of Pacific salmon (250 g c overed with 50 g tomato sauce) were evaluated experimentally during thermal processing in static retorts. Processing of salmon packaged in SPC require d around half of the time required for CMC, with both center-point and surf ace cook values reduced by factor of about two. Increasing the shape factor Phi, (0.68 for SPC and 0.82 for CMC) increased the heating (f(n)) and cool ing (f(c)) rate indexes. Processing temperature had a prevailing effect on heating and cooling lag factors (j(h) and j(c)), F-0, C-0 and C-0/F-0. The type of heating medium employed in this study was not a significant factor for most of the heating parameters. From the perspective of product quality and energy savings, the best processing conditions were achieved at high-t emperature short-time processing of salmon packaged in SPC.